That's the reason why they release another wide prime - with a 20mm though..

Yep. Just like every manufacturer that ever released a 28mm prime did so to cover the fact that their 24mm primes were total failures. Because after all, nobody in their right mind would offer *2* wide primes.

I think it also points out that the CZ24 is a total failure, because it's close to 20mm, too.